Activities in IO Land:

• installed PRM and PR2 irises
• first real issue
  • found huge signals in IMC/ASC signals for all IMC optics
• tracked this down to the IMC flashing enough to trigger the ASC, which pushed the optics
• this feature was disabled - see alog 39319
• optic sanity restored, aligned the beam to the IMC using the PZT
• noticed MC2 Trans at 30 counts - has been 1.6 to 2-ish counts without flashing
• noticed that PSL-Periscope-Power-In remained unchanged from yesterday
• was unsure of the power coming from the PSL
• closed the shutter to investigate
• found two beams on the bottom periscope mirror
• the first red herring of the day
  • the iris, which I found fully open, is the beam dump for the second beam, when the iris is about 1/2 closed
• tweaked the AOM beam alignment to maximize PSL periscope power, it increased from 0.06 to something (will alog later)
• this new alignment was centered on the iris/beam dump that's before the HWP that's before the bottom periscope mirror
• a issue to be looked at later
  • measured the power at the bottom periscope mirror - the current power into the IMC is 170mW
  • this is not accurately represented by any current DC PD signal
• exited the PSL
• aligned the beam to the IMC
• found the reason for the second red herring - MC2 trans SUM increase
  • while checking the MC2 iris, found the strong work light was on at the chamber, and when turned off, MC2 trans returned to it's normal values
• aligned the IMC to flash
• optic motion prevented all but a sparse few 0-0 flashes
• without 0-0 mode flashes, IMC and IM optic alignment through HAM2 will be difficult
• unclear what changed (reboots, restarts, mechanical...)
• see alog 39328
• will resume investigation/alignment tomorrow morning

- Cheryl, JeffK, Ed